I’ve been digitizing old family photos for a few years now. When I started, I used an Epson flatbed scanner – an Epson Perfection V550 – which scanned negatives as well as photographs. Later I bought a better Epson scanner, the V850, which is a higher-end model. I like these scanners, but I was a little disappointed with the sharpness of the smallest details. A few years back, I tried digitizing slides and negatives with a digital camera (a Panasonic Lumix GH5). I also used it to digitize some printed photographs and documents. The results from the camera seemed pretty good to me, so I thought I’d do a detailed comparison of the two methods.

For the subject, I wanted something with very fine lines. I was going to use a banknote, but the scanning software didn’t like that. Instead, I used an old Canadian stamp.

Goose stamp

Scanner

Using the Epson scanner, I scanned the stamp at various resolutions – 200, 300, 400, 600, 1200, 2400, 3600, and 6400 dpi, which is the maximum resolution for this scanner. Of course, files become much larger as the resolution increases. The scan of stamp at 200 dpi took up a fraction of a megabyte. At 6400 dpi, it was 216 megabytes. Scanning also becomes proportionally slower as the resolution is increased – the highest resolution scan of this small stamp took 1 minute 23 seconds.

Here’s a section  from scans of the stamp taken at different resolutions. You can see a steady improvement in quality as we move up from 200 dpi to 1200 dpi.

Epson 200 dpi

Epson 300 dpi

Epson 400 dpi

Epson 600 dpi

Epson 1200 dpi

Going further, there’s a small nudge in quality from 1200 to 2400, but after that, even zooming in very close on the original files and looking at the finest details, I can’t see any further improvement in quality, although the files become much larger as the resolution increases. The maximum quality seems to be somewhere between 1200 and 2400. You can click on the images to see a larger version. These are just JPEGs, but they are representative of the original files.

Epson 2400 dpi

Epson 3600 dpi

Epson 6400 dpi

Camera

You can’t adjust resolution on a camera on a menu the way you can on a scanner, but you can move the camera nearer or further to see more details. This camera’s sensor is 5184 pixels wide by 3888 pixels high, so if an object 1 inch wide fills the frame, the resolution will be 5184 dpi. If you move further away so an object 4 inches wide fills the screen, the resolution will be 1296 dpi. I’ve done some calculations so these camera images were taken in scanner-style numbers. Each of these is only a photograph, so it doesn’t take any longer to snap a higher resolution photo than one in a lower resolution. I haven’t adjusted any colours, so the camera has a whiter lighting. Here’s what the same area of the stamp looks like as the camera gets closer to the stamp.

GH5 600 dpi

GH5 800 dpi

GH5 1000 dpi

GH5 1200 dpi

GH5 3200 dpi

At about 1200 dpi, the camera image is roughly comparable to the highest image quality from the scanner. At 3200 dpi, the camera is still picking up more details. For example, there’s a tiny H in the right corner of the stamp. Here it is digitized by the camera at 3200 dpi and by the scannera at 6400 dpi.

GH5 3200 dpi

Epson 6400 dpi

As you can see, the camera picks up finer details, including the grain of the paper, texture which is a blur on the scanner. Again, this shows that the maximum effective resolution of the scanner is significantly lower than 3200 dpi.

So… should I digitize photos and documents with a camera or a scanner?

I liked the camera approach. It requires more fiddling, but it’s fast and the results (if you don’t screw up the focus) are great. It’s clear that a digital camera can deliver an image that is sharper than one from a very good scanner. But that doesn’t mean the camera is necessarily a better choice. It depends on a few other factors.

Size of objects

I was scanning a very small object here. In practice, with normal-sized objects, both camera and scanner will good quality results. If you’re scanning a typical photo at 600 dpi, this scanner will do fine. In fact, most scanners will do fine.The limitations of flatbed scanners become more obvious when you scan very small images – for example, slides, or film negatives. The scanner can’t match the detail you get from a camera with a macro lens. If you go smaller still in scale – scanning 8mm film, for example – the gulf becomes even more obvious, as they are in that “H” shot. At the opposite end of the scale, the scanner can manage documents up to about 8.5 x 11 inches, but no larger. The camera can take in a wider image – a photo of a broadsheet newspaper page will be at a resolution of about 250 dpi, which is quite readable.

Colour quality

I was also looking only at resolution and detail, which is just one aspect of image quality. It’s possible the scanner may reproduce colour more accurately, or have a better dynamic range (be able to pick out details in dark or light areas. The numbers for colour depth and dynamic range are better for this scanner than they are for my camera… although after comparing the results for resolution, I do wonder if the numbers can be believed.

Focus

A scanner should give an even focus over the entire image. This isn’t always true with a camera, and you will have to do some extra work to get focus right in the first place, or it will be blurred all over. In my case, I found that the automatic focus usually did an excellent job, and the lens (an Olympus M.Zuiko 30 mm f/3.5 macro) delivered an image that was sharp from corner to corner. The camera’s kit lens (12-35 mm) would have a harder time getting this close, but reproductions of larger documents and printed photographs looked very good with that one too, and was also sharp.

Speed

If you’re digitizing a large number of images, the camera is faster, and can take the pictures as fast as you can put them down. If your camera has a permanent home on a copy stand, it will be quick and easy to take a new photo. If not, there will be some minutes of setup time before you can get started. It also takes extra time to transferring images from camera to computer. A scanner will usually take 20 or 30 seconds per scan, but it is permanently connected to a computer and saves the files directly. For smaller or more occasional scanning jobs, the flatbed scanner may be a better choice. If you’re making dozens or hundreds of reproductions, the camera becomes much faster. (Although if you’re scanning standard sized documents, both camera and flatbed scanner will be easily outpaced by a speedy duplex document scanner like the Fujitsu ScanSnap series.)

Space requirements

The camera setup usually takes up more space. You need lights, a location where stray light won’t interfere with the image, some sort of camera stand, and a table for your documents. The scanner takes up space on a desk, but lights are self-contained. It’s usually a more compact package.

Price

The camera is a more expensive setup. You need a camera, a lens, a set of lights, and some sort of copy stand or jib arm, so you can mount the camera directly above your documents. You may also want accessories like a shutter release (so you can take a photo without touching the camera) and an AC power supply, so you’re not constantly changing camera batteries. It can be done on the cheap, but even then, it won’t be cheaper than the scanners bundled with a typical all-in-one printer.